And pile on they did, bringing their tools with them. They seized the levers, and in a moment the car was spinning down the track. There was something fascinating and invigorating in the motion. As they pumped up and down, Allan could see the fields, fences, and telegraph-poles rushing past them. It seemed to him that they were going faster even than the “flier.” The wind whistled against him and the car jolted back and forth in an alarming way. “Hold tight!” yelled Reddy, and they flashed around a curve, across a high trestle, through a deep cut, and down a long grade on the other side. Away ahead he could see the chimneys of the town nestling among the trees. They were down the grade in a moment, and whirling along an embankment that bordered a wide and placid river, when the car gave a sudden, violent jolt, ran for fifty feet on three wheels, and then settled down on the track again. “Stop her!” yelled the foreman. “Stop her!” They strained at the levers, but the car seemed alive and sprang away from them. Twice she almost shook them off, then sullenly succumbed, and finally stopped. “Somethin’s th’ matter back there!” panted Jack. “Give her a shove, Reddy!” Reddy jumped off and started her back up the track. In a moment the levers caught, and they were soon at the place where the jolt had occurred. The foreman sprang off and for an instant bent over the track. Then he straightened up with stern face. “Quick!” he cried. “Jerk that car off th’ track and bring two fish-plates an’ some spikes. West, take that flag, run up th’ track as far as y’ kin, an’ flag Number Six. Mind, don’t stop runnin’ till y’ see her. She’ll have her hands full stoppin’ on that grade.” With beating heart Allan seized the flag and ran up the track as fast as his legs would carry him. The thought that the lives of perhaps a hundred human beings depended upon him set his hands to trembling and his heart to beating wildly. On and on he went, until his breath came in gasps and his head sang. It seemed that he must have covered a mile at least, yet it was only a few hundred feet. And then, away ahead, he saw the train flash into sight around the curve and come hurtling down the grade toward him.